Interesting video about the 285K. It does have the plastic stitch regulator knob and lifter. The bottom is also made the way shown in the video. The one I bought is actually like new, and maybe that is it, but I don't find it all that loud. It is not the quietest machine I have, but it is also not the loudest. I currently have roughly 30 machines. It is a straight stitch machine and I what I want it for is to piece quilts or simple sewing and it will be just fine for that. It has a perfect stitch. I didn't have to do anything to it other than put in a light bulb. I think it is definitely worth the $10 I paid and I wouldn't have thought $20 to be awful either. Guess the machine is lucky I'm the one who stumbled across it.
I did go look at a 185J several months ago that was listed on CL. It was in awful shape. The lady said she only used it for decor and she didn't know if it worked or not. It didn't and the machine itself was broken like someone must have dropped it. Personally I think she knew it didn't work.